Motor driven hand tool



Feb. 24, 1942. E. M. HOOVER 2,274,443

MOTOR DRIVEN HAND TOOL Filed June 24, 1940 1a Z9 5' I 22 27 gwwm' EdwardHook)? Patented Feb. 24, 1942 MOTOR DRIVEN HAND TOOL- Edward M. Hoover,Anderson, Ind., assignor to H and H Research Company, Detroit, Mich., acorporation of Michigan- Application June 24, 1940, Serial No. 342,171

1 Claim.

This invention relates to certain new and useful improvements in motordriven hand tools. The primary object of the invention is to provide amotor driven hand tool and while designed for various uses, isespecially adaptable for use by die makers and engravers for thefinishing of dies and the like.

A further object ofthe invention is to provide a motor driven hand toolof the foregoing char: acter wherein the rotary motion driven shaft isconverted into reciprocatory movement so that the tool may be used forfiling, chipping, routing, cutting and the like.

With the above and other objects in view that will become apparent asthe nature of the invenbroken away and shown in section with the bevelgear drive illustrated at right angles to the position shown in Figure2. 1

Referring more in detail to the accompanying drawing, the motor drivenhand tool comprises a motor casing 5 preferably of cylindrical formationto. form a hand grip, the casing 5 housing a motor 6 that has a shaft 7journalled in a bearing 8 in the cross-wall 9 adjacent one end of thecasing 5. The other end of the casing carries a removable cap itpermitting access to the motor 6 and which cap carries a tubular boss llprojecting outwardly therefrom and through which boss and cap a flexibleelectric conductor l2 extends. The motor 6 is controlled in itsoperation by the switch button I3 projecting through a side wall of thecasing 5.

As shown in Figures 2 and 3, the cylindrical wall of the casing 5carries a cylindrical extension M beyond the end wall 9 to provide a rchamber I5 forwardly of the wall 9 that is closed at its outer end by aremovable cap having an end wall l6 and an annular side wall I1telescopically mounted upon the extension wall It. A tubular bearing l8projects outwardly of the end wall l 6 of the cap in axial alignmentwith the bearing 8 in the wall 9 and the motor shaft 1.

A stub shaft I9 is disposed radially of the chamber l5 and is mounted inthe extension wall [4 of the motor casing 5 and the side wall I! of thecap for securing the cap in position on the motor case extension, theinner end of the shaft l9 having a disk 20 mounted thereon to provide asupport for a bevel gear 2| journalled upon the inner terminal end ofthe shaft 19. The bevel gear 2| is disposed for meshing engagement witha bevel pinion 22 secured to the end of the motor shaft 1 that projectsinto the chamber l5. A stub shaft 23 is reciprocably mounted in thetubular bearing l8 projecting outwardly from the end wall of the cap l6and a pitman rod 24 has one end thereof pivotally attached as at 25 tothe inner end of the stub shaft 23 while the other end of the pitman rod24 has a pivotal eccentric mounting 26 with a side face of the bevelgear 2. A chuck arrangement designated in general by the referencecharacter 21 is carried by the outer end of the stub shaft 23 for thereception and support of a tool 28 of a preferred character. Inassembling the tool parts, the cap l6 receives the stub shaft 23, pitman24, bevel gear 21 and gear supporting disk 20. The cap is then placed onthe extension wall M of the motor casing 5 and the stub shaft I9 is theninserted in the registering openings in the extension wall l4 and sidewall I! of the cap for positioning engagement with the supporting disk20 and gear 2| and further acts to retain the cap I 6 upon the motorbody.

Tools for accomplishing such operations as filing, chipping, routing,cutting and the like may be mounted in the chuck arrangement 21 andrenvertheless to be understood that minor changes may be made thereinwithout departing from the spirit and scope of the invention as claimed.

I claim:

In a motor driven hand tool, wherein a casing has a partition walltherein adjacent one end defining a motor chamber and a mechanismchamber, wherein a closure cap for the outer end of the chamber has anend wall with a tubular bearing projecting outwardly thereof and a sidewall inclosing the wall of the mechanism chamber, wherein a motor andshaft are disposed in the motor chamber, wherein the partition wall hasa bearing therein for the motor shaft with the latter projecting intothe mechanism chamber, wherein a bevel pinion is fixed on the projectingend of the motor shaft, wherein a stub shaft is reciprocably mounted inthe tubular bearing carried by the cap, wherein a bevel gear in

